Therapeutic use

Model
Digital Document
Publisher
Florida Atlantic University
Description
Prostate cancer is one of the leading causes of death in men aged 40-55. Genistein isoflavone (4', 5', 7-trihydroxyisoflavone) is a dietary phytochemical with demonstrated anti-tumor activities in a variety of cancers. Topotecan Hydrochloride (Hycamtin) is an FDA-approved chemotherapy drug, primarily used for secondary treatment of ovarian,cervical and small cell lung cancers. This study was to demonstrate the potential anticancer activities and synergy of topotecan-genistein combination in LNCaP prostate cancer cells. The potential efficacy and mechanism of topotecan/genistein-induced cell death was investigated... Results: The overall data indicated that i) both genistein and topotecan induce cellular death in LNCaP cells, ii) topotecan-genistein combination was significantly more efficacious in reducing LNCaP cell viabiligy compared to either genistein or topotecan alone, iii) in all cases, cell death was primarily through apoptosis, via the activation of the intrinsic pathway, iv) ROS levels were increased and VEGF expression was diminished significantly with the topotecan-genistein combination treatment, v) genetic analysis of topotecan-genistein treatment groups showed changes in genetic expression levels in pathway specific apoptotic genes.... Conclusion: Treatments involving topotecan-genistein combination may prove to be an attractive alternative phytotherapy of adjuvant therapy for prostate cancer.
Model
Digital Document
Publisher
Florida Atlantic University
Description
The projects described in this dissertation are focused on compounds derived from the marine environment. Chapter 1 gives an introduction to the study of marine natural products to treat human ailments and a thorough review on compounds from lithistid sponges that have been isolated or synthesized since 2000. Chapter 2 describes the isolation and structure elucidation of two sesquiterpene substituted benzoquinone derivatives, petrosiquinones A and B, from a deep-water marine sponge from the Family Petrosiidae. Although initially purified following activity in a (Sb(B-catenin/Tcf4 assay they were later followed using tumor cell line cytotoxicity assays. Petrosiquinone A was the more active of the two compounds with moderate cytotoxicity in the DLD-1, PANC-1, and AsPC-1 cell lines. In Chapter 3, the isolation and structure elucidation of two new marine-derived macrolides, madeirolide A and B, isolated from a deep-water lithistid sponge of the genus Leiodermatium is described.
Model
Digital Document
Publisher
Florida Atlantic University
Description
The purpose of this research is to compare the surface dose outside the treatment area for different breast cancer irradiation modalities using Thermoluminescence Dosimeters (TLDs). Five different modalities are included in this study: Accuboost, Photon boost, Electron boost, Strut-Adjusted Volume Implant (SAVI), and Mammosite Multi-lumen (ML).Six points of interest (POI) on the breast cancer patients had been selected for the TLDs placement. Data from 25 breast cancer patients at Lynn Cancer Institute of the Boca Raton Regional Hospital were included in the study. The measured percentage ranges of the averaged doses at the six POIs for the different modalities are: Sternum 0.26% - 3.26%, Shoulder 0.33% - 2.79%, Eye 0.26% - 1.32%, Thyroid 0.20% - 2.75%, CLB 0.2% - 5.46%, Lower Abdomen 0.16% - 2.25%.
Model
Digital Document
Publisher
Florida Atlantic University
Description
Cone snails are carnivorous marine mollusks, utilizing their neuropeptide-rich venom for prey capture. The venom of Conus brunneus, a wide-spread Eastern Pacific vermivore, has not been extensively studied. In the current work, peptides from the dissected venom were characterized and tested using preliminary bioassays. Six peptides (A-F) were isolated and tested. Three peptide identities were determined by comparison with previously reported data: bru9a (A), bru3a (F), and an a-conotoxin (E). Preliminary screening in a stroke-related model of induced glutamate excitotoxicity in primary neuronal cells and PC12 cell cultures indicated potential neuroprotective activity of peptide fractions A, D, and F. Further testing is necessary to determine and verify structure, activity, target, and mechanism of action of the promising peptides from C. brunneus, which may prove effective neuropharmacological agents to treat stroke.
Model
Digital Document
Publisher
Florida Atlantic University
Description
Vitamin D insufficiency/deficiency is widespread in asthma, and epidemiological studies point to an association between low serum 25-hydroxyvitamin D level and poor asthma control and increased severity. In humans. Vitamin D is principally derived from sunlight induced cutaneous conversion of 7-dehydrocholesterol to vitamin D and oral supplementation. We sought to determine if established and chronic-persistent adult asthma patients from a South-Florida pulmonary patient population, with abundant sunshine availability and oral vitamin D supplementation exhibit vitamin D insufficiency/deficiency. A trend to vitamin D insufficiency was observed in approximately 65% of both adult asthma patients and apparently healthy (non-asthmatic) volunteers. . The transcription factors required for Th9 conversion, PU.1 and IRF-4, were down-regulated by vitamin D. The generation of Th9 cells was inhibited equally by vitamin D and dexamethasone when used alone, but the effect was additive when both steroids were used in combination. Our studies using non-specifically stimulated cells were extended by analyzing the effect of vitamin D on allergen specific stimulation. The response of CD4+ T cells obtained from the blood of house dust mite positive asthmatics was studied. House dust mite allergen elicited a classical Th2 phenotype response (IL-4, IL-5, IL-9, and IL-13 cytokine profile) and vitamin D effectively inhibited those key Th2 cytokines. We conclude that vitamin D appears to be of significant clinical benefit in our cohort of patients, i.e., established chronic adult human asthma, by down-regulating key immune cells including Th9, Th17, and Th2 involved in this disorder.
Model
Digital Document
Publisher
Florida Atlantic University
Description
With antimicrobial resistance to current drugs steadily rising, the development of new antibiotics with novel mechanisms of action has become an imperative. The majority of life-threatening infections worldwide are caused by "ESKAPE" pathogens which are encountered in more than 40% of hospital-acquired infections, and are resistant to the majority of commonly used antibiotics. Naturally occurring cyclic depsipeptides, microbial secondary metabolites that contain one or more ester bonds in addition to amide bonds, have emerged as an important source of pharmacologically active compounds or lead structures for the development of novel antibiotics. Some of those peptides are either already marketed (daptomycin) or in advanced stages of clinical development (ramoplanin). Structurally simple, yet potent, fusaricidin/LI-F and lysobactin families of naturally occurring antibiotics represent particularly attractive candidates for the development of new antibacterial agents capable of overco ming infections caused by multidrug-resistant bacteria. These natural products exhibit potent antimicrobial activity against a variety of clinically relevant fungi and Gram-positive bacteria. Therefore, access to these classes of natural products and their synthetic analogs, combined with elucidation of their mode of action represent important initial steps toward full exploitation of their antmicrobial potential. This dissertation describes a general approach toward the solid-phase synthesis of fusaricidin/LI-F and lysobactin analogs and an extensive structure-activity relationship (SAR) study. We have devised a simple and robust preparation strategy based on standard Fmoc solid-phase peptide synthesis protocols.
Model
Digital Document
Publisher
Florida Atlantic University
Description
Current research in natural products has heavily focused on the identification of potent biologically active compounds, specifically for drug development. The project detailed in this thesis focuses on the extraction of compounds from marine invertebrates as well as defining the absolute configuration for a compound. Utilizing marine invertebrates, the sonications method developed in this thesis provides an alternative approach to rapidly extract compounds for primary screening. This method is viable compared to a traditional overnight extraction method, without suffering compound degredation... Previously, clathric acid was isolated from an unknown Clathria sp. This compound is a bibyblic C-21 terpenoid shown to have mild antimicrobial activity against gram positive bacteria. With only its relative configuration established, additional amounts of clathric acid were required to define the overall absolute configuration. Identifying the Clathria sp. to be Clathria compressa, through spicule analysis, additional sponge tissues were then collected off the coast of Boca Raton, Florida to isolate additional quatities of clathric acid. The absolulte configuration was determined through circular dichroism and the octant rule to establish a final configuration for clathric acid's four carbon stereocenters to be: (3S, 7S, 8R, and 12S).
Model
Digital Document
Publisher
Florida Atlantic University
Description
A Monte Carlo model has been developed using MCNP5 to simulate the Nucletron Ir-192 HDR source in order to investigate the influence of tissue heterogeneities on dose calculations compared to the dose in homogeneous water media, as it is typically calculated by brachytherapy Treatment Planning Systems (TPS). Validity of the simulation was verified in water medium in comparison with peer reviewed results using the dosimetric parameters recommended by AAPM, Task Group-43. The dose-rates in simulated prostate, bladder and rectum were compared to those obtained in the homogeneous water phantom. Based on the resulting dose differences, it is inferred that TPS algorithms for brachytherapy dose calculations overestimate the dose to tissues like prostate and bladder by up to 49%. A clinically relevant dose underestimation of 5.5% to the rectum was also found. We recommend that further investigation using actual patient CT data as input to the Monte Carlo simulation be performed.
Model
Digital Document
Publisher
Florida Atlantic University
Description
The current study utilized a quasi-experimental nonequivalent groups design to investigate whether a 5-week long Mindfulness Meditation Intervention (MMI), would impact measures of attention, positive and negative affect, state and test anxiety, mindfulness, and reactive cortisol levels in 107 school aged children. A series of reliability corrected ANCOVAs were performed on all behavioral variables. Results indicated that those in the MMI group did not differ from their cohorts on any of the behavioral measures. Reactive levels of salivary cortisol were also collected and assayed in a subsample of 25 participants. An ANCOVA on cortisol change scores was performed and findings did not reach statistical significance. Post-hoc power analyses revealed that this could be due to inadequate sample size. To conclude studies utilizing a MMI of longer duration or with larger sample sizes may be required in assessing the usefulness of MMIs in behavioral and physiological measures in non-clinical child populations.
Model
Digital Document
Publisher
Florida Atlantic University
Description
This study investigated potential apoptotic and anti-proliferative effects of the phytochemicals, genistein and anthocyanin extract, as single and combined treatments in MCF-7 human breast cancer cells. Cells were exposed to single and combined treatments with the phytochemiclas for 48 and 72 hours. Cell viability was assessed using the MTT bioassay. Apoptosis induction was assessed using acridine orange ethidium bromide and rhodamine 123 ethidium bromide fluorescence assays. Both singe and combination treatments induced dose- and time-dependent apoptotic cell death in MCF-7 cells. The percentage of apoptosis was higher in combination treatments than single treatments with either phytochemical, although the difference was not statistically significant. The combination of genistein and anthocyanin extract peaked in efficacy at 48 hours of treatment, to exhibit significantly greater (P<. O5) dose- and time-dependent cell cytotoxicity than single treatments. This study reveals potential chemopreventive implications for the complementary effects of genistein and anthocyanin extract.